Crimping 45 colt brass

[markp]

I am loading 45 colt . I have winchester and starline brass with rcbs carbide dies.  The part I have never
felt comfortable with is crimping. I always  seem to take off a thin strip of brass around the case mouth
probally shortening the brass life. What am I doing wrong ?  This is hornaday xtp bullets with a nice
cannelure. I suspect I am setting the crimping die too low ?

[Sweetwater]

I'll take a stab at your question with a question -

(1) Is the "thin strip of brass" from the case mouth or from the base of the bullet and you see it at the case mouth?

You are loading jacketed bullets and it "appears" to me that "maybe" the cases are not belled enough and the case mouth is peeling a strip off the corner of the base of the bullet as it enters the case.
 
I've done that in the past with pistol calibers until I learned the fine art of "enough bell". "Enough bell" is when you can set the bullet inside the very edge of the case mouth by hand, and have it sit there. Not enough and the bullet will wobble or fall off as you raise the ram to seat the bullet.

(2) Are your case mouths chamferred on the inside or "square-cut"?

A square-cut case mouth will be on a new case or a newly trimmed case and will peel a small strip off the corner of the base of a bullet, expecially if there is not enough bell.

Chamferring takes off the square edge of the inside of the case mouth and aids in seating the bullet.

Hope that helps.

Regards,
Sweetwater

[John Traveler]

Another reason that you may be having crimping problems is that the bullet seating and crimping should be done as separate operations.  That's right:  seat all your bullets first, then back off the seater stem, and bring the crimping shoulder down to crimp the case.

Trying to do both seating and crimping in the same operation is counterproductive because as the crimping shoulder is applied, the bullet seater stem tries to seat the bullet further into the case, and the case mouth either has to dig into a new place on the bullet cannelure, or it scrapes a ring of bullet material out.

Do the operations separately and see what a difference it makes!

[Lloyd Smale]

Johns got the right answer

[Glanceblamm]

(2) Are your case mouths chamferred on the inside or "square-cut"?

A square-cut case mouth will be on a new case or a newly trimmed case and will peel a small strip off the corner of the base of a bullet, expecially if there is not enough bell.

Chamferring takes off the square edge of the inside of the case mouth and aids in seating the bullet.

This is another good point in addition to John Travelers post.

That's right:  seat all your bullets first, then back off the seater stem, and bring the crimping shoulder down to crimp the case.

I do this but the only thing that I dont like about it is that I dont like to disturb the crimpt setting once I get it set where I want it. Therefore, I often work with small lots (say no more than 200 rounds) of seated
bullets because they have to be ran through the seating/crimp die again. I do go as far as to make a small reference mark with a lead pencil and a straight edge on top of the die body for reference to future reloads and can often get that die set backup to within 1/16th of an inch or less. This Might Sound Redundant Or being picky but IMO, consistancy is everything.

The answer might be to purchase something like the Lee Factory Crimp die but I seem to be doing ok without one. If you operate the ram lever carefully for the first few rounds once you find your setting, you can (feel) the amount of crimp that you are getting. We do change to diff bullet types of course so I like to start light and advance that die just 1/8 turn at a time like the Inst say and once again, when you get to where you want to be it is easy to (feel) too light, too heavy, or just right.

[markp]

  Thanks for all the responces guys.  I appretiatie it a lot.
   A couple thoughts.

  I do seat and then back off the seater to  crimp as a seperate function. So I dont think its the seating
  as I dont seem to notice  the shaved brass until after the crimp.  But I am going to dbl check after seating to be sure.
  I dont really undestand chamfered or square cut ? The brass has been used and not trimmed.

 I am going to print out this page for referance/ cross check  when I have time to reload again.
 I try to have the edge of the brass about center of the cannlure ?

    Can it be To much pressure when crimping ?  To clarifiey the thin strip  usually appears at the outside of the case mouth . I have to do it again and pay more attention to small detail.

You guys are great .
Thanks


 
 

  Thanks   

[Sweetwater]

"I dont really undestand chamfered or square cut ? The brass has been used and not trimmed."

A chamferring tool from RCBS, FORSTER, LYMAN, HERTERS, etc is a double ended piece of round machine stock. Almost looks like a tiny rocket ship from the Buck Rogers days. The tool is used, either by hand or chucked in a drill or lathe type power tool. The pointed end will taper the inside of the case mouth. The inverted end (looks like the legs under a rocket) will clean the outside edge of the case mouth. They are about 3" long and 1" in diameter.

If your casemouth looks like it has a sort of knife edge, then it has been chamferred. If you can see a flat surface where the case was "cut" when produced, then it hasn't been chamferred.

One note: be very judicious when chamferring the outside of a case you want to crimp, as you want to leave a good edge there to crimp with. Just lightly dress the outside edge to clean up any cuttings from trimming, etc.

On the crimping, you can "feel" the crimp into place as you adjust the crimping die. Don't over-do it. You are not crimping a hard kicking round, so a heavy crimp is probably unwarranted. I seat my bullets to where the casemouth is at the top of the crimping groove. The case will be a tad shorter after crimping and I like the crimp groove "filled" so to speak. It is a "what do I want" kind of adjustment. Many ways are the right ways and you have to find what works for you.

I read some bad stuff about using a Lee Factory Crimp Die on revolver cases, and that they were great on rifle cases. My experience has shown that I like them on the rifle cases and my jury is still out on using them with revolver cases.

I ran some over the chronograph yesterday, and I really think the LFCD tightened the group a bit, though not dramatically. I was shooting 2" or less groups at 50ft offhand, and the last was with the LFCD batch and maybe cut 1.25", again offhand at 50ft.

The book says "don't shot offhand over a chronograph, as you might hit and damage the chronograph." My 49th shot out of a 50shot batch showed up at twice the normal velocity on the readout. The bullet cut the wire that joins the two skyscreens, clipped the top of the case that holds the 2nd light, and punched a nice half-caliber slot in the top edge of my Chrony. Just like the book said I would.

We pulled the screw out that retains the 2nd light, tapped the Chrony case back into shape with a brass hammer and backing block, and soldered the wires back together. Shot #50 was within the same velocity spread as the rest of the batch, so I'm guessing it is OK, at least for now.

Imprssive what a 215grWFNPB can do in a 41Mag Marlin rifle at 1470fps 10ft from the muzzle (where the Chrony was!) This same load does 1150fps in my 5.5" Ruger Bisley Blackhawk. Mild, very pleasant and accurate from my standards. I'm not a bench-rest shooter.

"Can it be To much pressure when crimping ?  To clarifiey the thin strip  usually appears at the outside of the case mouth . I have to do it again and pay more attention to small detail."

Still sounds like it's from the bullet, not the case, but let us know what you find!

Regards,
Sweetwater

[markp]

  Thanks sweetwater !  When I get after it again I will try to see if I can figure it out and update.

  I made the mistake years ago of selling both my 41 mags. One was a 6 inch model 57 smith  and other a 6 1/2 inch ruger blackhawk. We sure do dumb things we wish we could undo in the span of a lifetime .
LOL